The folks at collision detection have an entry about a couple of British geneticists who sat down and wrote up a theory about the chromosonal implications of how people end up being either a Wizard or a Muggle in the Harry Potter universe. From the books we know that a witch or wizard can be born from two magical parents, two non-magical parents, or a mixture of both called a half blood. From that the two Brit scientists sat down and penned up a letter to the journal Nature on the subject of A Darwinian explanation of the Harry Potter’s inheritance of magical abilities.
This suggests that wizarding ability is inherited in a mendelian fashion, with the wizard allele (W) being recessive to the muggle allele (M). According to this hypothesis, all wizards and witches therefore have two copies of the wizard allele (WW). Harry’s friends Ron Weasley and Neville Longbottom and his arch-enemy Draco Malfoy are ‘pure-blood’ wizards: WW with WW ancestors for generations back. Harry’s friend Hermione is a powerful muggle-born witch (WW with WM parents). Their classmate Seamus is a half-blood wizard, the son of a witch and a muggle (WW with one WW and one WM parent). Harry (WW with WW parents) is not considered a pure-blood, as his mother was muggle-born.
There may even be examples of incomplete penetrance (Neville has poor wizarding skills) and possible mutations or questionable paternity: Filch, the caretaker, is a ‘squib’, someone born into a wizarding family but with no wizarding powers of their own.
Not to be outdone, three other scientists sent off letters disputing the theory. According to CD they wrote:
Noting that “Hermoine’s parents were muggle dentists who lack any family history of wizarding,” they find “the assumption that wizarding has a genetic basis to be deterministic and unsupported by available evidence.”
It’s all tongue in cheek though the original scientists were engaging in more than a flight of fantasy with their letter. Specifically they felt that the theory they’d come up with would be a great way to teach the rather difficult science of genetics to school kids in a manner they could relate to. The Potter universe offers a unique opportunity to teach about DNA and inheritance via the whimsical theory they had come up with. As CD notes, this could just be tossing fuel on the fire:
But this also, of course, implies the teaching of evolution, which makes you wonder which will be the bigger reason for the evangelical right to hate J. K. Rowling: Because she’s indoctrinating kids in witchcraft—or in Darwinian science?
Still, pretty cool stuff and one more way to get science across to kids in an interesting manner. Something we could use more of.